Islam joined the Bangladesh Civil Service in the Administration cadre in 1983.[5] He held several administrative roles during his career, including Magistrate, Upazila Nirbahi Officer, Land Settlement Officer, and Additional Deputy Commissioner.[5] He later worked in the Ministry of Education as the Project Director of a large education project supported by multiple development partners.[5] The project aimed to improve access to quality education and promote the use of digital tools in schools.[5]
In 2014, Islam was appointed the Secretary (Coordination and Reforms) in the Cabinet Division.[6] He was involved in efforts to reform public administration in line with the national goal of building a more inclusive and citizen-focused government.[5]
Islam was involved in the creation and rollout of the National Integrity Strategy, which aims to reduce corruption and improve ethical standards in public service.[5] He also chaired the inter-ministerial working group on the implementation of the Right to Information Act and helped promote access to public information.[5] In addition, he introduced updated versions of Citizen’s Charters and launched an online Grievance Redress System to make it easier for citizens to report problems and receive solutions.[5]
In August 2016, Islam was appointed commissioner of the National Human Rights Commission.[2][7] He interrogated the owner and manager of Raintree Hotel after an incident of rape at the hotel as head of the commission's fact-finding team.[8] From 2 July 2019 to 6 August 2019, he served as the acting chairman of the National Human Rights Commission.[7]
In 2020, Islam joined Vital Strategies as the country director for Bangladesh.[3] After the fall of the Sheikh Hasina led Awami League government, he was sued in a murder case along with 53 former secretaries of the government of Bangladesh.[9]